Radio frequency switch circuit

Abstract

The invention discloses a radio frequency switch circuit comprising a switch tube which is at least related to the on state and the off state of the radio frequency switch circuit; the parallel branch is connected with the switching tube in parallel; the parallel branch comprises a first inductor, the first inductor spirally surrounds the switching tube from one end of the switching tube to the other end of the switching tube with the switching tube as the center axis, and the extending direction of the center axis is perpendicular to the thickness direction.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application filed with the Intellectual Property Office of the People's Republic of China on December 25, 2024, with application number PCT / CN2024 / 142486 and invention name "A Radio Frequency Switching Circuit", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present invention relates to the field of radio frequency technology, and in particular to a radio frequency switching circuit. Background Art

[0004] In the patent application number PCT / CN2024 / 142486, by setting a first inductor in the parallel branch of the switching tube, the off-state capacitance of the switching tube can be reduced, thereby improving the RF performance.

[0005] However, since the first inductor is located in the parallel branch of the switching tube, the area of the RF switching circuit is increased, resulting in lower integration. In addition, the quality factor of the first inductor in the above patent is difficult to reach 10, which in turn affects the performance of the RF switching circuit.

[0006] In view of this, how to increase the quality factor of the first inductor to above 10 while reducing the area of the above-mentioned RF switch circuit has become a technical problem that needs to be solved urgently. Summary of the Invention

[0007] The embodiments of the present invention provide a radio frequency switching circuit to solve the above-mentioned technical problems existing in the prior art.

[0008] In a first aspect, to solve the above technical problems, an embodiment of the present invention provides a radio frequency switching circuit, comprising:

[0009] A switch tube, wherein the switch tube is at least related to an on state and an off state of the radio frequency switch circuit;

[0010] A parallel branch is connected in parallel with the switch tube; the parallel branch includes a first inductor, which spirals from one end of the switch tube to the other end of the switch tube with the switch tube as the central axis, and the extension direction of the central axis is perpendicular to the thickness direction.

[0011] In a possible implementation manner, the first inductor includes:

[0012] A first lead-out portion, a main body, and a second lead-out portion are connected in sequence; the main body takes the switch tube as the central axis and spirally wraps around from one end of the switch tube to the other end of the switch tube, and the first lead-out portion and the second lead-out portion are arranged in the same layer or different layers.

[0013] In a possible implementation manner, the body includes:

[0014] In the thickness direction, a plurality of first line segments and a plurality of second line segments are located on different sides of the switching tube; the plurality of first line segments are parallel to each other and arranged in the same layer, the plurality of second line segments are parallel to each other and arranged in the same layer, and the orthographic projections of the two ends of the second line segments on the plane where the plurality of first line segments are located coincide with different ends of two adjacent first line segments in the plane; wherein the arrangement direction of the plurality of first line segments and the plurality of second line segments is the extension direction of the central axis;

[0015] A plurality of connecting line segments; at a position where the first line segment and the second line segment overlap, the connecting line segments connect the first line segment and the second line segment.

[0016] In a possible implementation manner, the first lead-out portion is provided on the same layer as one of the first line segment and the second line segment;

[0017] The second lead portion is provided in the same layer as one of the first line segment and the second line segment.

[0018] In a possible implementation manner, one of the first lead portion and the second lead portion is connected to one of the first electrode of the switching tube and the second electrode of the switching tube;

[0019] The other of the first lead portion and the second lead portion is connected to the other of the first pole and the second pole.

[0020] In a possible implementation manner, the parallel branch further includes a frequency modulation device, and the frequency modulation device is used to reconstruct the operating frequency of the radio frequency switch circuit;

[0021] One of the first lead portion and the second lead portion is connected to one of the first pole and the second pole;

[0022] The other of the first lead-out portion and the second lead-out portion is connected to an end of the frequency modulation device close to the first inductor; and an end of the frequency modulation device away from the first inductor is connected to the other of the first pole and the second pole.

[0023] In one possible implementation manner, the radio frequency switch circuit further includes:

[0024] The connection structure is located at the position where the lead-out portion overlaps with the connected first pole or second pole, and the connection structure is connected between the lead-out portion and the first pole or the second pole; the lead-out portion includes the first lead-out portion or the second lead-out portion.

[0025] In a possible implementation manner, the first lead portion and the second lead portion are respectively parallel to line segments provided in the same layer, and the line segments include the first line segment or the second line segment;

[0026] Alternatively, the extending directions of the first lead portion and the second lead portion respectively intersect with the extending directions of the line segments provided in the same layer.

[0027] In a possible implementation manner, an arrangement direction of the first pole of the switching tube and a second pole of the switching tube is the same as an extension direction of the central axis.

[0028] In one possible implementation, the first electrode, the second electrode, and the gate of the switching tube all have comb-tooth structures, and the comb-tooth structure used by the first electrode and the comb-tooth structure used by the second electrode are meshed with each other; the comb-tooth structure includes a plurality of strip-shaped comb teeth and a connecting portion, and the connecting portion is connected to the same end of the plurality of strip-shaped comb teeth;

[0029] The strip-shaped comb teeth of the gate are located between the strip-shaped comb teeth of the first electrode and the strip-shaped comb teeth of the second electrode, and the total number of the strip-shaped comb teeth of the gate is less than the total number of the strip-shaped comb teeth of the first electrode;

[0030] An extending direction of the strip-shaped comb teeth is the same as an extending direction of the central axis, and an arrangement direction of the plurality of strip-shaped comb teeth is orthogonal to the extending direction of the central axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of a radio frequency switching circuit in the related art;

[0032] Figure 2 is an equivalent circuit diagram of the radio frequency switch circuit in the on state;

[0033] Figure 3 is the equivalent circuit diagram of the radio frequency switch circuit in the closed state;

[0034] Figure 4 This is a curve diagram of insertion loss-Q value of a switching tube;

[0035] Figure 5 A graph showing the isolation-Q value of a switching tube;

[0036] Figure 6 Schematic diagram of a planar spiral inductor;

[0037] Figure 7 The Q value-frequency curve of the planar spiral inductor is shown in FIG.

[0038] Figure 8 The insertion loss-frequency curve corresponding to the switch tube of the parallel planar spiral inductor;

[0039] Figure 9 The isolation-frequency curve corresponding to the switch tube of the parallel planar spiral inductor is shown;

[0040] Figure 10 A three-dimensional schematic diagram of a radio frequency switching circuit provided by an embodiment of the present invention;

[0041] Figure 11 A schematic structural diagram of another radio frequency switch circuit provided by an embodiment of the present invention;

[0042] Figure 12 A Q value-frequency curve diagram of a first inductor provided in an embodiment of the present invention;

[0043] Figure 13 Insertion loss-frequency curve of a radio frequency switch circuit provided by an embodiment of the present invention;

[0044] Figure 14 An isolation-frequency curve diagram of a radio frequency switch circuit provided in an embodiment of the present invention;

[0045] Figure 15 A schematic diagram of a radio frequency switching circuit provided by an embodiment of the present invention;

[0046] Figure 16 A schematic structural diagram of another radio frequency switch circuit provided by an embodiment of the present invention;

[0047] Figure 17 A schematic structural diagram of another radio frequency switch circuit provided by an embodiment of the present invention;

[0048] Figure 18 A schematic diagram of a radio frequency switch circuit according to an embodiment of the present invention;

[0049] Figure 19 A schematic diagram of forming a switch tube provided by an embodiment of the present invention;

[0050] Figure 20 A schematic diagram of forming a connection structure provided by an embodiment of the present invention; Description of the drawings:

[0052] Switch tube T, parallel branch P, first inductor L1, frequency modulation device F, first pole T s , the second pole T d , Gate T g , active layer T a , strip-shaped comb teeth S1, connecting portion S2, base substrate 1, buffer layer 2;

[0053] First lead portion L11, body L12, second lead portion L13, first line segment a, second line segment b, connecting line segment c, connecting structure J, first insulating layer 3, second insulating layer 4, gate insulating layer GI, gate connecting structure T g ', first pole connection structure T s ', the second pole connection structure T d ', interlayer insulation layer IDL. DETAILED DESCRIPTION

[0054] An embodiment of the present invention provides a radio frequency switching circuit to solve the above-mentioned problems existing in the prior art.

[0055] It should be understood that the specific structural and functional details disclosed in the embodiments of the present invention are merely representative and are for the purpose of describing exemplary embodiments of the present application. However, the present application can be implemented in many alternative forms or combinations and should not be construed as being limited to the embodiments described herein.

[0056] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly indicate the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, the term "including" and any variations thereof are intended to cover non-exclusive inclusions.

[0057] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0058] The terms used in this application are intended only to describe specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "a", "an", "an item" used herein are also intended to include the plural. It should also be understood that the terms "comprise" and / or "include" used herein specify the presence of stated features, integers, steps, operations, units and / or components, and do not exclude the presence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0059] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention will be further described below with reference to the accompanying drawings and examples. However, the example embodiments can be implemented in various forms and should not be understood as being limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concepts of the example embodiments to those skilled in the art. The same figure marks in the figures represent the same or similar structures, and their repeated descriptions will be omitted. The words expressing position and direction described in the present invention are all explained with reference to the accompanying drawings as examples, but changes can be made as needed, and the changes made are all included in the scope of protection of the present invention. The drawings of the present invention are only used to illustrate the relative position relationship and do not represent the true proportion.

[0060] It should be noted that specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. The subsequent description of the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application and is not intended to limit the scope of the present application. The scope of protection of the present application shall be determined as defined by the appended claims.

[0061] See Figure 1 This is a schematic diagram of a radio frequency switching circuit in the related art. Figure 1 The RF switching tube circuit includes:

[0062] RF input terminal in and RF output terminal RF out ;

[0063] The first thin film transistor T1, the source and drain of the first thin film transistor T1 are respectively connected to the radio frequency input terminal RF in and RF output terminal RF out connect;

[0064] The second thin film transistor T2, the source of the second thin film transistor T2 and the radio frequency input terminal RF in Connecting, the drain of the second thin film crystal is grounded;

[0065] The first resistor R1 is connected to the gate of the first thin film transistor T1 and the first control terminal V G1 Between; first control terminal V G1 for receiving a first signal for controlling the first thin film transistor T1 to be turned on or off;

[0066] The second resistor R2 is connected to the gate of the second thin film transistor T2 and the second control terminal V G2 Between; the second control terminal VG2 Used to receive a second signal for controlling the second thin film transistor T2 to be turned on or off.

[0067] When the first control terminal V G1 The first signal received is high level, and the second control terminal V G2 When the received second signal is at a low level, the first thin film transistor T1 is turned on, the second thin film transistor T2 is turned off, and the RF input terminal RF in The input RF signal is transmitted to the RF output terminal RF through the first thin film transistor T1. out At this time, the RF switch is turned on and the RF signal is conducted.

[0068] On the contrary, when the first control terminal V G1 The first signal received is low level, and the second control terminal V G2 When the received second signal is at a high level, the first thin film transistor T1 is turned off, the second thin film transistor T2 is turned on, and the radio frequency signal is conducted to the ground via the second thin film transistor T2. At this time, the radio frequency switch is turned off.

[0069] When the thin film transistor is turned on, it is equivalent to a resistor (denoted as R on ), and when the thin film transistor is turned off, it is equivalent to a capacitor (C off ), the smaller the two values, the better, R on ×C off It can indirectly reflect the radio frequency performance of the thin film transistor. The equivalent resistance (R on ) is calculated as follows:

[0070]

[0071] Where μ is the mobility of the channel material of the thin film transistor, C ox is the capacitance of the gate insulating layer of the thin film transistor, W and L are the channel width and length of the thin film transistor respectively, V gs and V th are the gate-drain voltage and threshold voltage of the thin film transistor respectively. Figure 2 and Figure 3 , Figure 2 is the equivalent circuit diagram of the RF switch in the on state, Figure 3 is the equivalent circuit diagram of the RF switch circuit in the closed state, where R T1 、R T2 The resistance equivalent to R on ), C T1 、C T2 The capacitance equivalent to C off ).

[0072] For glass-based thin-film transistors, due to low-temperature processes and lattice matching, the mobility of the channel material of the thin-film transistor is relatively low. For example, the mobility of low-temperature polysilicon (LTPS) is about 100 cm 2 / (V·s), which is higher than the mobility of single crystal silicon (about 1400cm 2 / (V·s)) is one order of magnitude smaller, which results in a larger on-resistance of the glass-based thin film transistor.

[0073] As can be seen from formula (1), the on-resistance of the thin film transistor can be reduced by increasing the width-to-length ratio W / L. However, increasing W / L will increase the parasitic capacitance of the thin film transistor, which will cause the RF performance of the thin film transistor to deteriorate, and thus cause the RF performance of the RF switch to deteriorate.

[0074] In the patent application number PCT / CN2024 / 142486, the RF performance of the RF switching circuit is improved by providing a parallel branch in parallel with the switching tube and allowing the parallel branch to include a first inductor.

[0075] When designing circuits, inductors are often considered ideal inductors with zero resistance, and their quality factor is therefore infinite. However, in reality, inductors have resistance. Therefore, according to patent application number PCT / CN2024 / 142486, the RF performance of the switching transistor deteriorates as the quality factor (Q value) of the first inductor decreases.

[0076] Please refer to Figure 4 and Figure 5 , Figure 4 This is a curve diagram of the insertion loss-Q value of a switching tube. Figure 5 This is a graph of the isolation-Q value of a switch tube. This switch tube works at 4.9GHz. Figure 4 It can be seen that if the insertion loss needs to be less than 0.6dB, the inductor Q value needs to be greater than 12.

[0077] Please refer to Figure 6 and Figure 7 , Figure 6 A schematic diagram of a planar spiral inductor. Figure 7 The Q value-frequency curve of the planar spiral inductor is shown in Figure 2. Figure 7 It can be seen that at 4.9 GHz, the Q value of the planar spiral inductor is 4.284, and the Q value of this planar spiral inductor is relatively low.

[0078] Please refer to Figure 8 and Figure 9 , Figure 8This is the insertion loss-frequency curve corresponding to the switch tube of the parallel planar spiral inductor. Figure 9 The isolation-frequency curve corresponding to the switch tube of the parallel planar spiral inductor is shown in Figure 2. Figure 8 It can be seen that when the RF switch tube operates at 4.9GHz, the insertion loss of the planar spiral inductor is 1.3dB, and the RF performance of the switch tube is poor.

[0079] In addition, the planar spiral inductor requires a large area, resulting in a low degree of integration of the RF switch circuit containing the planar spiral inductor.

[0080] To solve the above problems, an embodiment of the present invention provides a radio frequency switch circuit, which is described in detail below with reference to the accompanying drawings.

[0081] Please refer to Figure 10 A three-dimensional schematic diagram of a radio frequency switching circuit provided by an embodiment of the present invention. The radio frequency switching circuit includes:

[0082] The switch tube T is at least related to the on state and the off state of the radio frequency switch circuit; when the radio frequency switch circuit is in the on state, the radio frequency signal input from the input end of the radio frequency switch circuit is output from the output end of the radio frequency switch circuit; when the radio frequency switch circuit is in the off state, the radio frequency signal input from the input end of the radio frequency switch circuit cannot be output from the output end of the radio frequency switch circuit;

[0083] A parallel branch P is connected in parallel with the switch tube T. The parallel branch P includes a first inductor L1. The first inductor L1 takes the switch tube T as the central axis and spirally wraps from one end of the switch tube T to the other end of the switch tube T. The extension direction of the central axis is perpendicular to the thickness direction.

[0084] exist Figure 10 In the example, the parallel branch P is composed of the first inductor L1. The two ends of the first inductor L1 are connected to the first electrode T of the switch tube T. s and the second pole T d connect.

[0085] Please refer to Figure 11 A schematic structural diagram of another radio frequency switching circuit provided by an embodiment of the present invention is shown. Figure 11 The switch tube T in the circuit is connected in parallel with the planar spiral inductor.

[0086] By comparison Figure 10 and Figure 11 It can be seen that in Figure 10 Since the first inductor L1 takes the switch tube T as the central axis and spirally wraps from one end of the switch tube T to the other end of the switch tube T, the extension direction of the central axis is perpendicular to the thickness direction, so that the area occupied by the first inductor L1 and the area occupied by the switch tube T are roughly overlapped, and Figure 11Since the area occupied by the planar spiral inductor does not overlap with the area occupied by the switch tube T, Figure 10 The RF switch circuit shown is relatively Figure 11 The RF switch circuit shown occupies a smaller area and has a higher integration density.

[0087] Please refer to Figure 12 A Q value-frequency curve diagram of a first inductor provided in an embodiment of the present invention, from Figure 12 As can be seen from the figure, the first inductor L1 is a three-dimensional inductor. When the frequency is 4.9 GHz, the corresponding Q value is 30. Therefore, the first inductor L1 is set to be centered on the switch tube T and spirally wound from one end of the switch tube T to the other end of the switch tube T. The extension direction of the central axis is perpendicular to the thickness direction. This can greatly improve the Q value of the first inductor L1 and make it greater than 10.

[0088] Please refer to Figure 13 and Figure 14 , Figure 13 The insertion loss-frequency curve of a radio frequency switch circuit provided by an embodiment of the present invention is as follows: Figure 14 This is an isolation-frequency curve diagram of a radio frequency switching circuit provided by an embodiment of the present invention. Figure 13 and Figure 14 The corresponding RF switching circuit is Figure 10 The RF switch circuit shown in the figure is Figure 13 It can be seen that when the RF switch circuit works at 4.9GHz, the corresponding insertion loss is 0.35dB, which is Figure 8 The insertion loss of the corresponding planar spiral inductor has been greatly improved; Figure 14 and Figure 9 Compared with the isolation of the corresponding planar spiral inductor, Figure 14 The isolation of the corresponding first inductor L1 is also greatly improved. Therefore, in the present invention, the first inductor L1 is set to take the switch tube T as the central axis, spirally wrapping from one end of the switch tube T to the other end of the switch tube T, and the extension direction of the central axis is perpendicular to the thickness direction. This can greatly improve the insertion loss and isolation of the RF switch circuit, thereby greatly improving the RF performance.

[0089] In the embodiment provided by the present invention, a parallel branch P including a first inductor L1 is provided for a switch tube T at least related to the on state and the off state of the RF switch circuit, and the first inductor L1 is spirally wound from one end of the switch tube T to the other end of the switch tube T with the switch tube T as the central axis, and the extension direction of the central axis is perpendicular to the thickness direction. This not only improves the Q value of the first inductor L1 to above 10, but also effectively reduces the area of the RF switch circuit, thereby improving the RF performance of the RF switch circuit while improving the integration of the RF switch circuit.

[0090] Please continue to refer to Figure 10 , the first inductor L1, including:

[0091] The first lead portion L11, the main body L12 and the second lead portion L13 are connected in sequence; the main body L12 takes the switch tube T as the central axis and spirals from one end of the switch tube T to the other end of the switch tube T. The first lead portion L11 and the second lead portion L13 are arranged on the same layer or different layers.

[0092] like Figure 10 As shown, the body L12 of the first inductor L1 is a spiral coil that spirals from one end of the switching transistor T to the other end of the switching transistor T with the switching transistor T as the central axis. The first lead portion L11 and the second lead portion L13 are arranged on the same layer, and in this case, they are both arranged on the same side of the switching transistor T. Of course, the first lead portion L11 and the second lead portion L13 can also be arranged on different layers, such as the first lead portion L11 and the second lead portion L13 can be respectively arranged on different sides of the switching transistor T. Whether the first lead portion L11 and the second lead portion L13 are arranged on the same layer or on different layers can be determined according to the film layer where the device connected to the first inductor L1 is located in the RF switching circuit, and is not limited here.

[0093] In the embodiment provided by the present invention, the first inductor L1 is configured to include a first lead portion L11, a body L12, and a second lead portion L13 connected in sequence; and the body L12 is spirally wound from one end of the switching tube T to the other end of the switching tube T with the switching tube T as the central axis. The first lead portion L11 and the second lead portion L13 are arranged on the same layer or different layers, which facilitates the wiring of devices connected to the first inductor L1.

[0094] Please continue to refer to Figure 10 , body L12, including:

[0095] In the thickness direction, multiple first line segments a and multiple second line segments b are located on different sides of the switch tube T; the multiple first line segments a are parallel to each other and arranged in the same layer, the multiple second line segments b are parallel to each other and arranged in the same layer, and the orthographic projections of the two ends of the second line segments b on the plane where the multiple first line segments a are located coincide with the different ends of two adjacent first line segments a in the plane; wherein the arrangement direction of the multiple first line segments a and the multiple second line segments b is the extension direction of the central axis;

[0096] A plurality of connecting line segments c; at a position where the first line segment a and the second line segment b overlap, the connecting line segment c connects the first line segment a and the second line segment b.

[0097] By always having multiple first line segments a and multiple second line segments b on different sides of the switch tube T, and the arrangement direction of the multiple first line segments a and the multiple second line segments b is the extension direction of the central axis, and making the two ends of the second line segment b coincide with the orthographic projection of the plane where the multiple first line segments a are located and the different ends of two adjacent first line segments a in the plane, and using a connecting line segment c to connect the first line segment a and the second line segment b at the position where the first line segment a and the second line segment b overlap, the body L12 switch tube T can be used as the central axis, spiraling from one end of the switch tube T to the other end of the switch tube T.

[0098] In some embodiments, the first lead-out portion L11 is disposed in the same layer as one of the first line segment a and the second line segment b; and the second lead-out portion L13 is disposed in the same layer as one of the first line segment a and the second line segment b.

[0099] like Figure 10 As shown, the first lead-out portion L11 and the second lead-out portion L13 are both arranged on the same layer as the second line segment b; in actual applications, the first lead-out portion L11 can also be arranged on the same layer as the first line segment a, and the second lead-out portion L13 can be arranged on the same layer as the second line segment b; or, the first lead-out portion L11 can be arranged on the same layer as the second line segment b, and the second lead-out portion L13 can be arranged on the same layer as the first line segment a or the second line segment b. Specifically, whether the first lead-out portion L11 and the second lead-out portion L13 are arranged on the same layer as the first line segment a or the second line segment b can be set according to wiring requirements.

[0100] Please continue to refer to Figure 10 One of the first lead portion L11 and the second lead portion L13 is connected to the first electrode T of the switch tube T. s and the second pole T of the switch tube T d A connection in

[0101] The other of the first lead portion L11 and the second lead portion L13 is connected to the first pole T s and the second pole T d Another connection in .

[0102] For example, Figure 10 When the parallel branch P is composed of the first inductor L1, the first lead portion L11 and the second lead portion L13 are connected to the first electrode T of the switch tube T respectively. s and the second pole T d connect.

[0103] Please refer to Figure 15 This is a schematic diagram of a radio frequency switch circuit provided by an embodiment of the present invention. The parallel branch P further includes a frequency modulation device F, which is used to reconstruct the operating frequency of the radio frequency switch circuit.

[0104] One of the first lead portion L11 and the second lead portion L13 is connected to the first pole T s and the second pole Td A connection in

[0105] The other of the first lead portion L11 and the second lead portion L13 is connected to the end of the frequency modulation device F close to the first inductor L1; the end of the frequency modulation device F away from the first inductor L1 is connected to the first pole T s and the second pole T d Another connection in .

[0106] By setting a frequency modulation device F in the parallel branch P and connecting one of the first lead portion L11 and the second lead portion L13 to the first pole T s and the second pole T d The other of the first lead portion L11 and the second lead portion L13 is connected to the end of the frequency modulation device F close to the first inductor L1; the end of the frequency modulation device F away from the first inductor L1 is connected to the first pole T s and the second pole T d Another connection in the circuit allows the frequency modulation device F to be connected in series with the first inductor L1, thereby utilizing the frequency modulation device F to reconstruct the operating frequency of the RF switching circuit, enabling the RF switching circuit to adapt to a wider frequency range while improving RF performance and integration, thereby increasing the applicability of the RF circuit.

[0107] In some embodiments, the frequency modulation device F may be a diode or an adjustable capacitor.

[0108] Please continue to refer to Figure 10 , the radio frequency switching circuit also includes:

[0109] The connection structure J is located at the lead-out portion and the first pole T connected s Or the second pole T d The connection structure J is connected based on the lead portion and the first pole T s Or the second pole T d the lead portion includes a first lead portion L11 or a second lead portion L13.

[0110] like Figure 10 As shown, the extension directions of the first lead portion L11 and the second lead portion L13 intersect with the extension directions of the line segments arranged in the same layer.

[0111] Please refer to Figure 16 A schematic structural diagram of another radio frequency switching circuit provided by an embodiment of the present invention.

[0112] The first lead portion L11 and the second lead portion L13 are parallel to the line segments provided in the same layer, and the line segments include the first line segment a or the second line segment b. This can reduce the distance between the first lead portion L11, the second lead portion L13 and the first pole T s Or the second pole T doverlapping area, thereby reducing parasitic capacitance.

[0113] Please refer to Figure 10 or Figure 16 , the first pole T of the switch tube T s and the second pole T of the switch tube T d The arrangement direction is the same as the extension direction of the central axis, which can reduce the first inductor L1 and the first pole T s and the second pole T d The overlapping area can reduce the parasitic capacitance.

[0114] Please continue to refer to Figure 16 , the first pole T s , the second pole T d and the gate T of the switch tube T g Both are comb-tooth structures, and the first pole T s The comb structure used and the second pole T d The comb teeth structure used are meshed with each other; the comb teeth structure includes a plurality of strip-shaped comb teeth S1 and a connecting portion S2, and the connecting portion S2 is connected to the same end of the plurality of strip-shaped comb teeth S1;

[0115] Gate T g The strip comb teeth S1 are located at the first pole T s The strip comb S1 and the second pole T d Between the strip comb teeth S1, and the gate T g The total number of strip comb teeth S1 is less than the first pole T s The total number of strip comb teeth S1;

[0116] The extending direction of the strip-shaped comb teeth S1 is the same as the extending direction of the central axis, and the arrangement direction of the plurality of strip-shaped comb teeth S1 is perpendicular to the extending direction of the central axis.

[0117] At the first pole T of the switch tube T s , the second pole T d and gate T g When the comb structure is adopted, the extension direction of the strip comb teeth S1 in the comb structure is the same as the color direction of the central axis, and the arrangement direction of the multiple strip comb teeth S1 is orthogonal to the extension direction of the central axis, which can reduce the first pole T of the switch tube T. s , the second pole T d and gate T g The overlapping area with the first inductor L1 is reduced, thereby reducing parasitic capacitance.

[0118] Please refer to Figure 17 This is a schematic structural diagram of another radio frequency switch circuit provided by an embodiment of the present invention, wherein the radio frequency switch circuit further includes:

[0119] Base substrate 1; a plurality of first line segments a are located on one side of the base substrate 1;

[0120] The first insulating layer 3 is located on a side of the plurality of first line segments a away from the base substrate 1; the switch tube T is located on a side of the first insulating layer 3 away from the base substrate 1;

[0121] The second insulating layer 4 is located on the side of the switch tube T away from the base substrate 1; multiple second line segments b are located on the side of the second insulating layer 4 away from the base substrate 1; the first insulating layer 3 to the second insulating layer has a through hole that penetrates the first insulating layer 3 to the second insulating layer, and the connecting line segment c connects the adjacent first line segment a and the second line segment b through the through hole.

[0122] By providing a first insulating layer 3 between the plurality of first line segments a and the switching tube T, and providing a second insulating layer 4 between the plurality of second line segments b and the switching tube T, the first insulating layer 3 and the second insulating layer 4 can be used to increase the distance between the first line segments a, the second line segments b and the switching tube T to prevent the first inductor L1 from affecting the switching tube T, and can also prevent the plurality of first line segments a and the plurality of second line segments b from being short-circuited with the conductive film layer in the switching tube T.

[0123] In some embodiments, a buffer layer 2 may be provided between the base substrate 1 and the first insulating layer 3 to enhance adhesion between the base substrate 1 and the plurality of first line segments a. The buffer layer 2 may be made of a stacked structure of silicon nitride and silicon oxide.

[0124] Please refer to Figure 18 A schematic diagram of a radio frequency switching circuit provided by an embodiment of the present invention.

[0125] S11: depositing a buffer layer 2 on one side of the substrate 1;

[0126] S12: sputtering a first metal layer on a side of the buffer layer 2 away from the base substrate 1, and patterning the first metal layer to obtain a plurality of first line segments a;

[0127] S13: forming a first insulating layer 3 on a side of the plurality of first line segments a away from the substrate 1;

[0128] S14: forming a switch transistor T on a side of the first insulating layer 3 away from the substrate 1;

[0129] S15: forming a second insulating layer 4 on a side of the switch tube T away from the substrate 1;

[0130] The second insulating layer 4 is made of materials including silicon nitride, silicon oxide, or other dielectric materials.

[0131] S16 : forming a plurality of second line segments b on a side of the second insulating layer 4 away from the base substrate 1 .

[0132] The first line segment a and the second line segment b are made of the same material.

[0133] Please refer to Figure 19 A schematic diagram of forming a switch tube provided by an embodiment of the present invention.

[0134] S141: forming a low-temperature polysilicon layer on the side of the first insulating layer 3 away from the substrate 1, and patterning the low-temperature polysilicon layer to obtain an active layer T a ;

[0135] The low-temperature polysilicon layer can be directly deposited by vapor phase deposition, or amorphous silicon can be deposited by vapor phase deposition and then crystallized by laser. The thickness of the low-temperature polysilicon layer ranges from 50nm to 300nm.

[0136] S142: In the active layer T a A gate insulating layer GI is formed on a side away from the base substrate 1 .

[0137] The gate insulating layer GI may be made of silicon nitride, silicon oxide, or other dielectric materials. Other dielectric materials may have a dielectric constant greater than that of silicon nitride (also known as silicon oxide), such as aluminum oxide, hafnium oxide, or other high-k dielectric constant materials. The thickness of the gate insulating layer GI ranges from 40 nm to 150 nm.

[0138] S143: forming a gate metal layer on the side of the gate insulating layer GI away from the substrate 1, and patterning the gate metal layer to obtain a gate T of the switch tube T. g ;

[0139] S144: Active layer T a Phosphorus ion self-aligned implantation is performed to implant the active layer T a The gate is not T g The covered part is ion doped to become a conductor, and the active layer T a The ion-doped parts at both ends serve as the first electrode T s and the second pole T d ;

[0140] S145: Etching the gate insulating layer GI and the first insulating layer 3 to form a plurality of first through holes H1 penetrating the gate insulating layer GI and the first insulating layer 3; the first through holes H1 overlap one end of the first line segment a; and filling the plurality of first through holes H1 with metal material to obtain a plurality of first sub-connecting line segments (not shown);

[0141] S146: At the gate T gAn interlayer insulating layer ILD is formed on a side away from the base substrate 1; a plurality of second through holes H2 are formed penetrating the interlayer insulating layer ILD, the plurality of second through holes H2 corresponding one-to-one to the plurality of first through holes H1, and the second through holes H2 are connected to the corresponding first through holes H1; and a metal material is filled in the plurality of second through holes H2 to obtain a plurality of second connecting line segments J (not shown);

[0142] The material of the interlayer insulating layer ILD includes silicon nitride, silicon oxide or other dielectric materials.

[0143] The thickness of the interlayer insulating layer ILD is in the range of 300 nm to 800 nm.

[0144] S147: Etching the interlayer insulating layer ILD and the gate insulating layer GI to expose the gate T g , a plurality of contact holes for the first electrode and the second electrode; forming a source and drain metal layer on the side of the interlayer insulating layer ILD away from the substrate 1, and patterning the source and drain metal layer to obtain a plurality of contact holes for the gate T through the contact holes; g The gate connection structure T g ', the first electrode connection structure T connected to the first electrode Ts through the contact hole s ', through the contact hole and the second pole T d The second pole connection structure T d '.

[0145] Please refer to Figure 20 A schematic diagram of forming connecting line segments provided by an embodiment of the present invention.

[0146] Obtain the first sub-connected line segment and the second sub-connected line segment through the aforementioned steps S15 and S16 respectively;

[0147] S15: etching the second insulating layer 4 to form a plurality of third through holes H3 penetrating the second insulating layer 4; the plurality of third through holes H3 correspond to the plurality of second through holes H2 one by one, and the third through holes H3 are connected to the corresponding second through holes H2;

[0148] S16: depositing a second metal layer on a side of the second insulating layer 4 away from the base substrate 1, and patterning the second metal layer to obtain a plurality of second line segments b and a plurality of third sub-connecting line segments (not shown) filled in the plurality of third through holes H3.

[0149] The first, second, and third sub-connecting line segments in the interconnected first through-hole H1, second through-hole H2, and third through-hole H3 constitute a connecting line segment connecting the first line segment a and the second line segment b. The first, second, and third sub-connecting line segments are made of the same material as the first and second line segments.

[0150] It should be noted that in Figures 17-20 In the figure, the first line, the second line and the switch tube T do not represent their relative position relationship in the actual cross-sectional view. The switch tube T, the first line and the second line are drawn in the same cross-sectional view just for the convenience of observation. Figure 19 and Figure 20 The first through hole H1 , the second through hole H2 , and the third through hole H3 shown in the figure do not actually penetrate the switch tube T.

[0151] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0152] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A radio frequency switching circuit, characterized in that: include: A switch tube, wherein the switch tube is at least related to an on state and an off state of the radio frequency switch circuit; A parallel branch is connected in parallel with the switch tube; the parallel branch includes a first inductor, which spirals from one end of the switch tube to the other end of the switch tube with the switch tube as the central axis, and the extension direction of the central axis is perpendicular to the thickness direction.

2. The radio frequency switching circuit according to claim 1, wherein: The first inductor includes: A first lead-out portion, a main body, and a second lead-out portion are connected in sequence; the main body takes the switch tube as the central axis and spirally wraps around from one end of the switch tube to the other end of the switch tube, and the first lead-out portion and the second lead-out portion are arranged in the same layer or different layers.

3. The radio frequency switching circuit according to claim 2, wherein: The body comprises: In the thickness direction, a plurality of first line segments and a plurality of second line segments are located on different sides of the switching tube; the plurality of first line segments are parallel to each other and arranged in the same layer, the plurality of second line segments are parallel to each other and arranged in the same layer, and the orthographic projections of the two ends of the second line segments on the plane where the plurality of first line segments are located coincide with different ends of two adjacent first line segments in the plane; wherein the arrangement direction of the plurality of first line segments and the plurality of second line segments is the extension direction of the central axis; A plurality of connecting line segments; at a position where the first line segment and the second line segment overlap, the connecting line segments connect the first line segment and the second line segment.

4. The radio frequency switching circuit according to claim 3, wherein: The first lead-out portion is provided on the same layer as one of the first line segment and the second line segment; The second lead portion is provided in the same layer as one of the first line segment and the second line segment.

5. The radio frequency switching circuit according to claim 4, wherein: One of the first lead portion and the second lead portion is connected to one of the first electrode of the switching tube and the second electrode of the switching tube; The other of the first lead portion and the second lead portion is connected to the other of the first pole and the second pole.

6. The radio frequency switching circuit according to claim 4, wherein: The parallel branch further includes a frequency modulation device, and the frequency modulation device is used to reconstruct the operating frequency of the radio frequency switch circuit; One of the first lead portion and the second lead portion is connected to one of the first pole and the second pole; The other of the first lead-out portion and the second lead-out portion is connected to an end of the frequency modulation device close to the first inductor; and an end of the frequency modulation device away from the first inductor is connected to the other of the first pole and the second pole.

7. The radio frequency switching circuit according to claim 5 or 6, characterized in that: Also includes: The connection structure is located at the position where the lead-out portion overlaps with the connected first pole or second pole, and the connection structure is connected between the lead-out portion and the first pole or the second pole; the lead-out portion includes the first lead-out portion or the second lead-out portion.

8. The radio frequency switch circuit according to any one of claims 2 to 6, wherein: The first lead portion and the second lead portion are respectively parallel to line segments provided in the same layer, and the line segments include the first line segment or the second line segment; Alternatively, the extending directions of the first lead portion and the second lead portion respectively intersect with the extending directions of the line segments provided in the same layer.

9. The radio frequency switch circuit according to any one of claims 1 to 6, wherein: An arrangement direction of the first pole of the switching tube and the second pole of the switching tube is the same as an extension direction of the central axis.

10. The radio frequency switching circuit according to claim 9, wherein: The first electrode, the second electrode, and the gate of the switching tube are all comb-tooth structures, and the comb-tooth structure used by the first electrode and the comb-tooth structure used by the second electrode are meshed with each other; the comb-tooth structure includes a plurality of strip-shaped comb teeth and a connecting portion, and the connecting portion is connected to the same end of the plurality of strip-shaped comb teeth; The strip-shaped comb teeth of the gate are located between the strip-shaped comb teeth of the first electrode and the strip-shaped comb teeth of the second electrode, and the total number of the strip-shaped comb teeth of the gate is less than the total number of the strip-shaped comb teeth of the first electrode; An extending direction of the strip-shaped comb teeth is the same as an extending direction of the central axis, and an arrangement direction of the plurality of strip-shaped comb teeth is orthogonal to the extending direction of the central axis.

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